Nov 30 GCHQ Royal Puzzle Question 4

This was favourite and I think it works out nicely enough that anyone with a logical brain and access to Google to fuel their hunches should be able to do it.

When we first gave up on question 3 we scrolled down the page and saw this and instantly divided it up for solving. Two of my students took 1 and 2 which we took as presumably Caesar Shift and Chemical symbols, while I took number 3 which looked like Tarot. If the Wikipedia page for Tarot hadn't been spectacularly unhelpful for Tarot then we would have been down within 3 minutes.

Number 1 is indeed a Caesar Shift, so if you shift all letters 2 places in the alphabet you get from each word to the next. 2 places on from the last is the word Prince.

Number 2 gives atomic numbers 9, 16, 25, 36, ? So we want the 49th element which is Indium, or In.

Looking up Tarot Card and then specialising for just the Occult Decks we get that there are 4 suits of 14 plus a Major Acana of 22 single cards each with a designated number. The wiki page of the Major Arcana gives their numbers as 1, 2, 4, 11, ?. We spent a long time trying to solve this sequence before we read the next sentence under the table on Wikipedia which said: "Strength is traditionally the eleventh card and Justice the eighth, but the influential Rider-Waite-Smith deck switched the position of these two cards in order to make them a better fit with the astrological correspondences worked out by the Hermetic Order of the Golden Dawn, under which the eighth card is associated with Leo and the eleventh with Libra." ... Good work Astrology, you've actually made me hate you more.

So the actual sequence should read: 1, 2, 4, 8, ?, so we get 16 which is The Tower.